Electrode alloy



Patented Pole. 28, 1933 entree srsr is ERWHE 1 LUWRY, 0B FOFJWT HILLS,FENIISYLVMHA, Assmrson '"Jl'tll ELEGTRIU 8c MANUFACTURING COHIA'LNY, ACQQJPQEJATIQN 333.

ELEGTEQDE MUTE? No Drawing. Application filed July so,

My invention relates to electrode alloys and especially to electrodealloys for glee discharge tubes employed in the reproduction andtransmission of pictures and sound.

An object of m invention is to provide on electlrode that Wi l sputtervery little or not at a 1.

Another object of my invention is to prolong the useful period of a tubeused as e, television-receiving tube b preventing sputterin at thecathode an concentration of the g ow at various points of said cathode.

More specificall 1 an object of my invention is to form the cat ode of atelevision-receiving tube out of a material that will not oppreciablysputter or have its glow concentrated at any particular point and solengthen the useful life of such tube to twenty or thirty times thelength of life otthe presout day television tube.

Other objects of my invention will become evident from the followingdetsiled description.

lel by a. distance substantially that of the mean free path of anelectron of the gee in the tube have been found to have a. very shortlife of ten or twelve hours of useful operation. Such a type of tube isdescribed in the copending application of Dewey Knowles, Serial No.337,699, filed February 5, 1929.

It has been found that the shortness of little of these tubes with lateelectrodes, genes ally of aluminum oxide, has been due plat/e sputteringwhile acting as the cathode. This sputtering of the cathode do posits afilm on the interior of the glass that gradually obscures the View ofthe glow the cathode. These aluminum oxide pistes also hove thedisadvantage that, if the is pierced at any point, a glow will concerntrete on said point and, therefore; will not be evenly distributed overthe surface of plate. According to my invention, 1 provide a, cathodeplate that will not sputter oppreciehly and will thus lengthen the lifeof the tube to two hundred or three hundred open to the ative hours inniece of the ten or twelve operative hours to which the tubes of theprior art were limited.

The material that l have found that produces this unexpected length oflife of the tube is a nickel-cobalt alloy and especially anickel-cobslt-iron alloy containing a meteriol such as titanium,zirconium or thorium which class of materials has an oniphoterichydroxide. The particular material of this class that l have founddesirable for use in the cathode is titanium.

Titanium, especially in the proportions such as is used in Konel metal,is particular ly suitable for use as cathode material in televisiontubes. The following preferred proportions are given by Way oi examplealthough the specific proportions might he voried Within certain limits.The composition is preferehly of Per cent Nickel M Cohelt M. 20 irons-.. M- new 33 Titanium ssssssssssss 2 These proportions rosy he vsriedas taught in my eopending epplicetion Serial filo. 03,664, filed @ctoher30 1929. As mentioned shove zirconium or thorium may he substituted forthe titanium.

This sired thickness. lit is first vocuum treated end then cleaned andpolished, as by running over a hurling Wheel. The plates ore then cut tothe desired size end ossenihied into the he tuhe then evseusted endfilled with l at less then atmospheric soch es noon at lainun mercurypresents. I

The polished oi lilonel hove ego oi. msintoening their high luster throu.hont the necessary handling in a U a u I cident to the mount-mg endseeling in the tuhe. Lenel else hes a. high mechanical strength whichprovides as. very rigid coninvention may he applied to tifoes oi othertypes Where it is desiied to reduce the sputtering of an electrodeindischsrge devices. As s' oeeiiic instances oi? such epplt silo isformed into pistes oi the de cation of the invention, 1. would mentionhot-cathode rectifiers, anodes in 'aseous dis charge rectifiers wherethe cathoc e was large in area and the anode correspondingly small inarea. and also glow lamps of various kinds, such as neon lamps for signsor in landingfield illumination. i-kccoi-dingly, I have discovered amaterial for the cathode plates of television tubes that, produces theunexpected result of lengthenin the lives of such tubes to twent orthirty times the average life of a tube ot the prior art.

My invention is not to be restricted except insofar as is necessitatedby the prior art and by the spirit of the appended claims.

I claim as my invention:

1. In an electrical glow discharge device an electrode having a surfacecomprising a nickel-cobalt alloy containing a material having anamphoteric hydroxide.

2. In an'elcctrical glow discharge device an electrode having a surfacecomprising a, nickel-cobalt alloy containing titanium.

3. In an electrical glow discharge device an electrode having a surfacecomprising a nicltel-eobalt-iron alloy containing a material having; ananiphoteric hydroxide.

4. In an electrical glow discharge device an electrode having a surfacecomprising a nickel cobalt-iron alloy containing titanium. A televisionlamp having a cathode having a surface consisting of a plate of anickel-cobalt alloy containing a material having an amphoteric hydroxideand an anode cooperating with said cathode.

6. A television lamp having a cathode having a. surface consisting of aplate of nickel-cobalt alloy containing titanium, and an anodecooperating with said cathode.

In testimony whereof, I have hereunto subscribed my name this 15th dayof July IRWIN F. LOWR-Y.

